长江、嘉陵江(重庆段)源水有机提取物的致突变活性及其季节变化

为了确定并比较重庆主城区段长江、嘉陵江源水有机提取物的致突变性及其季节变化规律，分别于春、夏、冬季采用GDX－120大孔树脂，对位于城区上游、城区中段、城区下游以长江、嘉陵江源水的5个水厂的进厂水进行了有机物的浓缩提取。提取物的致突变活性采用经典的Ames试验平板掺入法评估，测试菌株为TA98及TA100，同时做加与不加S9的比较。结果显示，嘉陵江及长江源水的有机提取物均有不同程度的致突变活性。嘉陵江源水明显大于长江源水，城区中段源水明显大于上游段及下游段源水。多数断面显示平水期致突变活较为显著并且移码型致突变性大于碱基置换型致密变性。研究结果提示，城市污染源已导致长江、嘉陵江源水具备致突变活性，控制两江沿岸的各种水污染源已成为当务之急。

Mutagenic activities and their seasonal changes of organic extracts from source water of Yangtze River and Jialing River in Chongqing section

In order to determine and compare the mutagenic activities of organic extracts from source water of Yangtze River and Jialing River in Chongqing section and their seasonal changes, the organic extracts were sampled with amberlite GDX-120 resin separately at five sites that located at upper, inner and down Chongqing city section of two rivers and seasonally at winter, spring and summer season. The mutagenic activities were determined according to Ames assay on strain TA98 and TA100, with or without S9 mix by plate incorporation method. The results showed that most of organic extracts from the two rivers were mutagenic at different degrees. In general, the extracts from Jialing River showed significantly stronger activity than those from Yangzte River, and the extracts from sites at inner city section showed more mutagenicity than those from upper and down city section. In most sites spring was the season in which source water exhibited highest mutagenicity. It is concluded that the pollution from city have led to the source water from Yangtze River and Jialing River being of the mutagenicity, and controlling source water pollution is very emergency to us.